Acouple of months ago, a feast of Irish food and drinks producers came to Covent Garden. Once the site of London's main fruit and vegetable wholesale market, just a cherry stone's throw from the Royal Opera House, Covent Garden now bubbles with a gallimaufry of street artists, shops, eateries and enough open space to host special events that draw crowds of tourists and Londoners working in the area.
The weather was particularly cruel but the mood was effervescent, bearing out my belief that the best tonic for low spirits is a week in the Emerald Isle. Second best is a few hours in the company of Irish people.
I rejoiced in the soft-lilting chatter, whiskey, steaming hot tea and slabs of well-buttered soda bread topped with wild smoked salmon or freshly grilled grass-fed beef. When the warmth and cheer of the Irish welcome had seeped right through me, stemming the icy cut of the wind, I found myself drawn to two great splodges of green located at either end of the market.
One was a stall selling pots of shamrock to plant in the garden, as effusively bushy as the clover patches in which I used to search in vain for four-leafed clovers as a child. The other sold an alternative kind of magic: sprouts, seeds and thimblefuls of the brightest, greenest potion imaginable. The potion was as hypnotically vivid and unreal as the contents of the bulbous glass jars that once stood in pharmacies, alongside mortar and pestle, above multi-drawered cabinets bearing labels in gilt lettered Latin.
The mother and daughter standing behind this second counter were clearly 21st-century women, not ancient apothecaries, but their Blarney Stone charm and their healthy good looks eventually persuaded me to try "a green sunlight transfusion".
If you believe that medicine only does good if it tastes awful, then a shot of wheatgrass ought to work miracles. I pinched my nose and downed the draught in one gulp, yet I still found it sickly sweet and disgusting, like liquid lawn clippings - which is, more or less, what it is.
To be precise, what the Butler family sells is organic spelt wheatgrass seeded in non-peat compost. The crop is cut in its youthful prime, when just a few centimetres high, and crushed to extract every last drop of its concentrated chlorophyll juices. These are claimed to heal, energise, rejuvenate and nourish, and are especially noted for purifying the blood, detoxifying the liver and cleansing the colon. No more than a small daily tot is recommended. Too much, I was relieved to hear, can be bad for you.
The trend for this sort of thing began in the US, of course. In farmers markets in California and New York recently, I saw vendors competing to sell trayloads of wheat and barley grass, like miniature lawns in seed trays, for ultra-fresh daily consumption at home by faithful fans. Addicts in need of an instant fix queued for shots processed on the spot.
The Butlers are happy to oblige the Irish and British markets, selling growing kits and special juicers to caterers, schools and home cooks keen to sow, reap and juice their own "elixir of life". Less than two years since launching their company, Good4U, in Northern Ireland, sales are soaring in Irish juice bars and health food shops, with the patrons of Nude, the trendy Dublin chain, leading the fashion pack.
You should be able to buy wheatgrass at Fresh & Wild in London and a leading English supermarket is expected to follow.
Much more to my taste are the seeds and sprouting shoots that supplement the wheatgrass business. The seeds (pumpkin, sunflower, linseed, sesame and poppy) are sold in various combinations - plain, toasted or thinly coated with vanilla sugar. They can be used in baking or sprinkled over breakfast cereals. They can also enrich salads or desserts and be eaten as snacks. Mini-packs designed for inclusion in lunchboxes could prove serious contenders for a slice of the lucrative crisps and confectionery market.
But the real stars of Good4U's range are their sprouting seeds, particularly a combination of broccoli, clover, alfalfa and radish called brocco shoots. Forget about fat, white, juicy, chop suey style beanshoots. Forget about neat little boxes of mustard (or rape) and cress whose contents lend pep to egg mayonnaise sandwiches. Brocco shoots boast a delicate spicy taste of their own and are as deliciously pretty as a wild tangle of fine hair.
Health food interest in such freshly germinated plantlets lies in their power-packed vitamin, mineral, enzyme and amino acid goodness. (Broccoli sprouts apparently contain up to 50 times more of the anti-cancer compound, sulforaphane, than mature broccoli.) I just like their sprightly fresh texture and taste. I find them fun to use and I relish their looks. Visually, they are the spun sugar of the vegetable world, making decorative garnish swirls that add appetising frivolity to, say, grilled steak, fishcakes, fried chicken and kedgeree. They also add zestful grace to salads, stir-fries and sandwiches.
Other companies sell sprouted seeds by mail order, expensively and not entirely satisfactorily. Good4U scores because the product is high quality and supremely fresh. It is well packaged and carries good background information. Shoots can be pulled day after day from the box, like silk hankies emerging from a conjuror's sleeve. Close the box properly, refrigerate it and the contents will keep for up to nine days.
Good4U's message is health oriented but its voice is neither hectoring nor faddy. Both packaging and website are colourful, lively and involving, attracting growing numbers who exercise and care about what they eat. The next stage is to encourage consumers to germinate seeds for themselves. "I want to take the message into primary schools," Bernie Butler explains. "Sprouting seeds in jam jars is nothing new but it could be the first step in helping to inspire and enthuse a new generation of gardeners and cooks, and encourage a taste for real fresh foods. The beauty is that seeds can be sprouted without access to garden space. The time lag between sowing and harvesting is not so long that youngsters will grow bored. And the crop can be enjoyed as soon as picked, with or without cooking."
It was a bright idea to label brocco shoots "nutritional superstars" and to describe the range as "21st-century smart foods". That is the sort of language today's youngsters respond to. Education delivered so palatably deserves to catch on.
www.good4U.co.uk
More columns at www.ft.com/davenport
